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Winter Wheat Yield Estimation Based on Sparrow Search Algorithm Combined with Random Forest:A Case Study in Henan Province,China
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作者 SHI Xiaoliang CHEN Jiajun +2 位作者 DING Hao YANG Yuanqi ZHANG Yan 《Chinese Geographical Science》 SCIE CSCD 2024年第2期342-356,共15页
Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous r... Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous research has paid relatively little attention to the interference of environmental factors and drought on the growth of winter wheat.Therefore,there is an urgent need for more effective methods to explore the inherent relationship between these factors and crop yield,making precise yield prediction increasingly important.This study was based on four type of indicators including meteorological,crop growth status,environmental,and drought index,from October 2003 to June 2019 in Henan Province as the basic data for predicting winter wheat yield.Using the sparrow search al-gorithm combined with random forest(SSA-RF)under different input indicators,accuracy of winter wheat yield estimation was calcu-lated.The estimation accuracy of SSA-RF was compared with partial least squares regression(PLSR),extreme gradient boosting(XG-Boost),and random forest(RF)models.Finally,the determined optimal yield estimation method was used to predict winter wheat yield in three typical years.Following are the findings:1)the SSA-RF demonstrates superior performance in estimating winter wheat yield compared to other algorithms.The best yield estimation method is achieved by four types indicators’composition with SSA-RF)(R^(2)=0.805,RRMSE=9.9%.2)Crops growth status and environmental indicators play significant roles in wheat yield estimation,accounting for 46%and 22%of the yield importance among all indicators,respectively.3)Selecting indicators from October to April of the follow-ing year yielded the highest accuracy in winter wheat yield estimation,with an R^(2)of 0.826 and an RMSE of 9.0%.Yield estimates can be completed two months before the winter wheat harvest in June.4)The predicted performance will be slightly affected by severe drought.Compared with severe drought year(2011)(R^(2)=0.680)and normal year(2017)(R^(2)=0.790),the SSA-RF model has higher prediction accuracy for wet year(2018)(R^(2)=0.820).This study could provide an innovative approach for remote sensing estimation of winter wheat yield.yield. 展开更多
关键词 winter wheat yield estimation sparrow search algorithm combined with random forest(SSA-RF) machine learning multi-source indicator optimal lead time henan province China
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Spatiotemporal Evolution and Influencing Factors of Urban-rural Construction Land in Rural Industrialized Areas in China:Case Studies in Changyuan City and Xinxiang County of Henan Province
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作者 SHI Yanwen LI Xiaojian +1 位作者 HU Xueyao LI Zeyi 《Chinese Geographical Science》 SCIE CSCD 2023年第5期850-864,共15页
Since China’s reform and opening up in 1978,the acceleration of industrialization and urbanization in China had led to dramatic changes in the pattern of urban-rural land use.In this paper,we focused on the rural ind... Since China’s reform and opening up in 1978,the acceleration of industrialization and urbanization in China had led to dramatic changes in the pattern of urban-rural land use.In this paper,we focused on the rural industrialized areas in central China(Xinxiang County and Changyuan City of Henan Province).We used the average nearest neighbor index,spatial statistical analysis,and a structural equation model to analyze the spatiotemporal evolution and influencing factors of urban-rural construction land based on multisource spatial data and survey data.The results showed that:1)from 1975 to 2019,the spatial distribution of urban-rural construction land in rural industrialized areas had evolved from homogeneous distribution to local agglomeration.In terms of comparative analysis of cases,the spatial distribution of urban-rural construction land in Changyuan City had shown a trend from diffusion to agglomeration,and Xinxiang County had overall shown a spatial change from homogenization to agglomeration and then to regional integration development.2)The hot spots with increased urban-rural construction land significantly expanded,and they had a high degree of spatial overlap with industrial development.Among them,Xinxiang County was concentrated in central and marginal areas,and Changyuan was mainly concentrated in central urban areas.3)From the evolution of spatial proximity of urban-rural construction land,rural industrialized areas generally decline,showing the characteristics of internal differentiation in the rate of change.4)Industrial development,social economy,the policy environment,and urban development played a positive role in promoting the expansion of urban-rural construction land in rural industrialized areas.To promote the optimal use of regional land and the integrated development of urban-rural areas,we should combine the advantages of regional endowment,formulate development strategies according to local conditions,and adjust the way that land is used in a timely manner. 展开更多
关键词 urban-rural construction land rural industrialized areas spatiotemporal evolution influencing factors rural industrialization henan province China
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Variations of Frost-free Period and Its Impact on Grain Yields in Henan Province during 1961-2013 被引量:4
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作者 闫军辉 傅辉 +1 位作者 周红升 徐新创 《Agricultural Science & Technology》 CAS 2015年第8期1588-1591,1692,共5页
The aim of this study was to investigate the responses of frost dates to global warming and its influences on grain yields. In this study, based on the frost date series defined by daily minimum ground temperature, th... The aim of this study was to investigate the responses of frost dates to global warming and its influences on grain yields. In this study, based on the frost date series defined by daily minimum ground temperature, the spatial and temporal characteristics of first frost date (FFD), last frost date (LFD) and frost-free period (FFP) were analyzed. The impact of extending FFP on major crop yields was also studied. The results were as follows: FFD showed a significantly delaying trend of 2.2 d/10 y, and LFD presented an advancing trend of 2.4 d/10 y. FFP extended at a rate of 4.5 d/10 y due to the later FFD and earlier LFD. The most obvious trend of FFD was in westem Henan, while the most significant trend of LFD and FFP oc- curred in south central parts of the study area. However, in eestem region, the trends of FFD, LFD and FFP were not so obvious. Major crop yield showed a sig- nificant correlation with frost-free period for Henan during 1961-2013. The yields of grain, rice, wheat, and maize increased by 79.5, 90.0, 79.5 and 70.5 kg/hm2 with FFP extending by one day. 展开更多
关键词 Daily minimum ground temperature Frost-free period Grain yield henan province 1961-2013
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Analysis of the Impact of Off-farm Employment of Agricultural Labor on Grain Production in Shandong Province and Henan Province 被引量:3
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作者 朱琳 刘彦随 《Agricultural Science & Technology》 CAS 2012年第7期1609-1615,共7页
[Objective] This study aimed to investigate the impact of off-farm employment of agricultural labor on grain production. [Method] Impact of off-farm employment of agricultural labor on grain production was investigate... [Objective] This study aimed to investigate the impact of off-farm employment of agricultural labor on grain production. [Method] Impact of off-farm employment of agricultural labor on grain production was investigated based on path analysis by using data from 200 counties and cities in Shandong Province and Henan Province in 2000 and 2008. [Result] Off-farm employment of agricultural labor affects grain production through agricultural land use patterns, off-farm employment of agricultural labor has negative impacts on grain production through multiple cropping index and positive impacts through the proportion of grain planting area. The positive impacts were greater in 2008. [Conclusion] Prerequisite of the positive impacts of off-farm employment on grain production is the substitution of agricultural mechanization development and agricultural technology advancement for agricultural labor. Orderly land circulation and scale land use should be promoted to avoid the lack of agricultural labor due to off-farm employment. 展开更多
关键词 Off-farm employment of agricultural labor Grain Production Path Analysis Shandong province henan province
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Technological Paths for Improving Grain Comprehensive Productivity ——Taking Henan Province for Instance 被引量:1
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作者 解宗方 张伟 《Agricultural Science & Technology》 CAS 2011年第10期1539-1542,1551,共5页
[Objective] This paper aimed at exploring technological paths for improving grain productivity based on the conditions and production practice in Henan Province.[Method] The status and dynamics of grain production in ... [Objective] This paper aimed at exploring technological paths for improving grain productivity based on the conditions and production practice in Henan Province.[Method] The status and dynamics of grain production in Henan Province were analyzed as a whole.[Result] The total production of grain in Henan Province had generally shown a tendency of ascent.Total grain production in Henan Province was 54 370 thousand t,which was 2.5 times of the total grain production in 1978,as 20 974 thousand t.The growth of grain production was more and more relying on the improvement of grain yield per unit area.[Conclusion] This research had provided theoretical basis for the improvement of grain production in Henan Province as well as for the grain production of the whole country. 展开更多
关键词 GRAIN TECHNOLOGY YIELD henan province
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Analysis of Driving Factors of Grain Output in Henan Province Based on Grey Correlation Model 被引量:1
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作者 贺振 《Agricultural Science & Technology》 CAS 2009年第3期123-126,147,共5页
Henan Province is an important grain production base, whose stable production is related to the economic development and social stability significantly. To summarize the primary factors of grain producing, we used gre... Henan Province is an important grain production base, whose stable production is related to the economic development and social stability significantly. To summarize the primary factors of grain producing, we used grey correlation analysis method to analyze 10 correlative factors such as grain yield, grain yield per unit area, effective irrigated area, rural employed persons, grain planting area, consumption of chemical fertilizer in 25 years. The results showed order of synthetic degree of incidence: effective irrigated area>rural electricity consumption>consumption of chemical fertilizer>disaster crop area>grain yield per unit of area>total power of agricultural machinery>afflicted crop area>grain planting area>number of the rural employed persons. Finally, according to synthetic degree of incidence between influential factors and total grain output respectively, a series of measures and the suggestions was proposed for grain production in Henan Province, which will also provide the scientific basis and help for the government correct decision-making. 展开更多
关键词 Grain yield Grey correlation analysis Driving force henan province
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Investigation and Analysis of Continuous Cropping of Flue-cured Tobacco in Henan Province
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作者 陈继峰 蔡凯旋 +4 位作者 孙会 赵松辉 刘洪源 石礼森 郑亚楠 《Agricultural Science & Technology》 CAS 2016年第8期1808-1812,1888,共6页
The continuous cropping of flue-cured tobacco in the major producing areas of Henan Province by designing questionnaire, fieldwork, enquiry and phone calls, mails, and other forms, the data were obtained then classifi... The continuous cropping of flue-cured tobacco in the major producing areas of Henan Province by designing questionnaire, fieldwork, enquiry and phone calls, mails, and other forms, the data were obtained then classified and analyzed. The results showed that the main planting areas of flue-cured tobacco were in Nanyang, Xuchang, Luoyang, Sanmenxia, Pingdingshan, and Luohe where were the major producing areas of succession cropping of flue-cured tobacco with percentage of 20%-40% for three years and over three years, and a few places up to 50%. Morbidity was common with wide distribution, and the main diseases were black shank, viral disease, and black rot. It proved that tobacco was not suitable for continuous cropping. Both of tobacco disease and pest rate and mortality significantly increased by more than 40% under continuous cropping for three years and over three years, and the yield and quality of flue-cured tobacco also decreased after continuous cropping. For many places, the tobacco yield started to decrease in the second year of continuous cropping, and after three-year cropping, the yield decreased in the range of 9%-24%. Continuous cropping for a long time would make a serious decline in the quality of tobacco, resulting in non-economic benefits. Therefore, in order to reduce the occurrence of diseases and economic loss in tobacco production, it is recommended to avoid continuous cropping, or to adopt appropriate measures to control tobacco continuous cropping obstacles in the unavoidable case. 展开更多
关键词 Flue-cured tobacco Continuous cropping YIELD QUALITY Diseases and pests INVESTIGATION henan province
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Pedigree and Trait Analysis of Soybean Varieties Registered in Henan Province
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作者 王树峰 卢为国 李卫东 《Agricultural Science & Technology》 CAS 2015年第11期2471-2475,共5页
To elucidate the genetic relationship of the soybean varieties registered in Henan province, we analyzed the pedigrees, the major agronomic traits, and the eco- nomic traits of 74 soybean varieties registered in Henan... To elucidate the genetic relationship of the soybean varieties registered in Henan province, we analyzed the pedigrees, the major agronomic traits, and the eco- nomic traits of 74 soybean varieties registered in Henan province from 1985 to 2012, with reference to experience and technologies beneficial to breeding. The resuits indicated that these varieties originated from 113 parents, and positive correla- tion between the yield and the number of original parents was significant. In the major agronomic traits, the growth stage was about 106 days with relatively small variation, while the final height varied largely among these varieties. Among the fac- tore affecting the final yield, the pod number per plant exhibited an increasing trend, while the variation of 100-grain weight was relatively small. More than 50% of the 113 original parents came from Henan Province and its neighbor provinces, and the genetic relationship among the registered varieties was too close. The rational criteria of yield components of soybean varieties in Henan Province should be as fol- lows: the pod number per plant was about 48. 6, with 100-grain weight ranging from 17.55 g to 21.80 g. 展开更多
关键词 SOYBEAN PEDIGREE Source of parent Agronomic characters Economic characters henan province
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Experimental Summary and Enlightenment of Urban and Rural Integration in Henan Province
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作者 张竟竟 陈文峰 +1 位作者 郭志富 鲁亚娟 《Agricultural Science & Technology》 CAS 2015年第3期622-625,共4页
By means of investigation and research of the 7 cities of the urban and rural integration in Henan Province, the paper summarizes five aspects of urban and rural integration in Henan Province in common from the social... By means of investigation and research of the 7 cities of the urban and rural integration in Henan Province, the paper summarizes five aspects of urban and rural integration in Henan Province in common from the social and economic conditions, spatial characteristics, dynamic mechanism, organization form, security measures: higher level of economic development, the selective advantage of location, the power mechanism characteristics of taking the government as the main body from top to bottom, the organization form of strengthen the construction of new rural area and industrial agglomeration area construction, the security measures of innovation mechanism system.The main sticking point to urban and rural integrition is the capital input and output, the rural collective economic power shortage problem , the problem of sustainable development of new rural community. A useful reference is playing the active role of rural cadre and masses initiative to promote the integration of urban and rural by injection power source from bottom to top; much channel solves problem of farmer employment according to local conditions; improve rural economy from hematopoietic function rely on industry development. 展开更多
关键词 The integration of urban and rural Construction of new countryside henan province
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Remote Sensing Dynamic Monitoring System for Agricultural Disaster in Henan Province Based on Multi-source Satellite Data
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作者 刘婷 王来刚 +1 位作者 左守亭 杨春华 《Agricultural Science & Technology》 CAS 2013年第1期155-161,共7页
Using 3S technology, relying on earth-space three-dimensional agriculture disaster monitoring network, remote sensing monitoring model for agricultural disaster in Henan Province was established, and agricultural disa... Using 3S technology, relying on earth-space three-dimensional agriculture disaster monitoring network, remote sensing monitoring model for agricultural disaster in Henan Province was established, and agricultural disaster monitoring system plat- form of Henan Province based on multi-souroe satellite data was further constructed, which realizes dynamic monitoring of agricultural disasters in Henan Province (drought, flood, snow cover and straw burning). 展开更多
关键词 Agricultural disaster Remote sensing monitoring 3S technology System application henan province
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The Application of ARIMA Model in Forecasting of PDSI in Henan Province
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作者 厉玉昇 《Agricultural Science & Technology》 CAS 2016年第3期760-764,共5页
[Objective] The aim was to establish drought forecasting model with high precision. [Method] With an ARIMA regression model, the research performed Palmer Drought mode(PDSI) time series modeling analysis of Henan Pr... [Objective] The aim was to establish drought forecasting model with high precision. [Method] With an ARIMA regression model, the research performed Palmer Drought mode(PDSI) time series modeling analysis of Henan Province based on PDSI time series and DPS(Data Processing Software) in order to build drought forecasting model. [Result] It is feasible to perform drought forecasting with appropriate parameters. [Conclusion] ARIMA model is practical and more precise in PDSI-based drought analysis and forecasting. 展开更多
关键词 ARIMA model PDSI Forecasting APPLICATION henan province
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Spatial-temporal Evolution and Driving Force of Cultivated Land Quality in Henan Province
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作者 宋艳华 《Agricultural Science & Technology》 CAS 2017年第11期2106-2112,2126,共8页
The purpose of this study was to find out the spatial-temporal rules and driving force of cultivated land quality in Henan Province in the last ten years. Agricultural land grading factor evaluation was used to evalua... The purpose of this study was to find out the spatial-temporal rules and driving force of cultivated land quality in Henan Province in the last ten years. Agricultural land grading factor evaluation was used to evaluate the cultivated land quality of 2002 and 2012 in Henan Province, and to research the change laws. Method of correlation coefficient was employed to select the driving forces affecting cultivated land quality evolution. The results indicated that the cultivated land quality in Henan Province increased slightly in the last ten years in general, and in spatial there were unchanged regions, increased regions and decreased regions. The cultivated land quality in spatial presented the trend of good becoming better, bad becoming worse, which should be highly valued in cultivated land quality protection and management. Land development and consolidation projects had significant contributions to increasing the cultivated land quality. Driving forces between the sudden change regions and gradual change regions were significantly different. The paper concluded that the research on the spatial-temporal evolution and driving force of cultivated land quality based on cultivated land quality evolution had important academic significance and practical value. 展开更多
关键词 Cultivated land quality Spatial-temporal evolution Driving force Sudden change region Gradual change region henan province
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Study on Land Use Regionalization in Henan Province
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作者 田燕 《Agricultural Science & Technology》 CAS 2017年第11期2139-2143,2184,共6页
According to the natural ecology and socio-economic conditions in Henan Province, a land use regionalization index system with 6 factors and 24 factor layers was constructed by combining with the characteristics of la... According to the natural ecology and socio-economic conditions in Henan Province, a land use regionalization index system with 6 factors and 24 factor layers was constructed by combining with the characteristics of land use in Henan Province. Expert scoring method was used to determine the weights of the indicators. Based on the similarities and differences of these factors in the index system at county (city, district) levels, hierarchical clustering method was used to make the quantitative analysis to the land use regionalization in Henan Province. And constrastive analysis and qualitative analysis were made to the regionalization scheme by combining with the acutal conditions in the counties (cities, districts), and finally, Henan Province was classified into 6 regions. 展开更多
关键词 Land use regionalization Index system Hierarchical clustering analysis method henan province
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Temporal and Spatial Analysis of Thunderstorms in 46 Years in Henan Province 被引量:3
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作者 韦丹 肖稳安 陈红兵 《Meteorological and Environmental Research》 CAS 2010年第9期42-45,共4页
By dint of natural orthogonal function(EOF) decomposition,correlation and trend analysis methods,the temporal and spatial variation characteristics of thunderstorms in recent 46 years in Henan Province were analyzed.T... By dint of natural orthogonal function(EOF) decomposition,correlation and trend analysis methods,the temporal and spatial variation characteristics of thunderstorms in recent 46 years in Henan Province were analyzed.The result showed that the thunderstorms in Henan Province decreased gradually from the northwest region to the southeast region and the frequency of thunderstorms in the southeast area was relatively high.The thunderstorm intensity area was in its horizontal distribution.Thunderstorms acted relative actively in 60s and tended to dwindle in the end of 80s.While in recent years,the thunderstorms tended to increase and started act frequently.Since March to August in every year,thunderstorms multiplied in each region and decreased after September.The period between 16:00 to 20:00 was the high peak hours of thunderstorms every year.Thunderstorms distribution in Henan Province had pretty good consistence,increasing and decreasing at the same time.The annual variation of thunderstorms showed an unobvious decreasing tendency. 展开更多
关键词 THUNDERSTORM Temporal-spatial variation henan province China
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LA-ICP-MS Zircon U-Pb Geochronology of Quartz Porphyry from the Niutougou Gold Deposit in Songxian County,Henan Province 被引量:17
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作者 WANG Zhongliang GONG Qingjie +2 位作者 SUN Xiang WU Fafu WANG Weixing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第2期370-382,共13页
The Niutougou gold deposit, located in the center of the Xiong'ershan gold district, western Henan Province, is a large gold deposit with many quartz porphyries found in the area. Based on the field geological invest... The Niutougou gold deposit, located in the center of the Xiong'ershan gold district, western Henan Province, is a large gold deposit with many quartz porphyries found in the area. Based on the field geological investigation of quartz porphyry of Niutougou gold deposit and by using the cathodoluminescence (CL) images analysis and in situ LA-ICP-MS U-Pb isotope dating method of zircons, the inner structure, trace element compositions and U-Pb age of the zircons separated from quartz porphyry were analyzed and determined. Cathodoluminescence (CL) images of zircons show clear magmatic zonations. Trace element analyses of zircons reveal that all zircons show high concentrations of Th, U, and HREE, and the REE patterns of depletion in LREE, with a positive Ce anomaly. Zircon LA-ICP-MS U-Pb dating results show that the quartz porphyry in the Niutougou gold deposit was formed at 159.714-0.99 Ma (about 160 Ma), belonging to the product of magmatic activity in late Middle Jurassic. Combined with the geological characteristics of the Niutougou gold deposit, the formation age of the quartz porphyry and the analysis of the formation age of the granite body exposed in the Niutougou gold deposit, the study suggests that the metallogenic epoch of the Niutougou gold deposit may be Yanshanian in age. 展开更多
关键词 quartz porphyry zircon U-Pb chronology Niutougou Songxian County henan province
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Cancer incidence and mortality in Henan province,2012 被引量:8
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作者 Shuzheng Liu Qiong Chen +5 位作者 Peiliang Quan Meng Zhang Shaokai Zhang Lanwei Guo Xibin Sun Chengzeng Wang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2016年第3期275-285,共11页
Objective: Population-based cancer registration data in 2012 from all available cancer registries in Henan province were collected by Henan Office for Cancer Research and Control. The numbers of new cancer cases and ... Objective: Population-based cancer registration data in 2012 from all available cancer registries in Henan province were collected by Henan Office for Cancer Research and Control. The numbers of new cancer cases and cancer deaths in Henan province with compiled cancer incidence and mortality rates were estimated. Methods: In 2015, all registries' data in Henan province were qualified for the national cancer registry annual report in 2012. The pooled data were stratified by area (urban/rural), gender, age group (0, 1-4, 5-9, 10-14, ..., 85+) and cancer type. New cancer cases and deaths were estimated using age-specific rates and corresponding population of Henan province in 2012. The Chinese census data in 2000 and Segi's population were applied for age-standardized rates. All the rates were expressed per 100,000 person-years. Results: Qualified 19 cancer registries (4 urban and 15 rural registries) covered 16,082,688 populations of Henan province in 2012. The percentage of cases with morphologically verified (MV%) and death certificate- only cases (DCO%) were 69.84% and 2.30%, respectively, and the mortality to incidence rate ratio (M/ I) was 0.64. It was estimated that there were 248,510 new cancer cases and 158,630 cancer deaths in Henan province in 2012. The incidence rate was 266.17/100,000 (288.61/100,000 in males and 241.86/100,000 in females), the age-standardized incidence rates by Chinese standard population (ASIRC) and by world standard population (ASIRW) were 208.95/100,000 and 206.41/100,000 with the cumulative incidence rate (0-74 years old) of 24.30%. The crude incidence rate in urban areas was higher than that in rural areas. However, after adjusted by age, the cancer incidence rate in rural was higher than that in urban areas. The crude mortality of all cancers in Henan province was 169.90/100,000 (201.23/100,000 in males and 135.95/100,000 in females). The age-standardized mortality rates by Chinese standard population (ASMRC) and by world standard population (ASMRW) were 131.20/100,000 and 130.80/100,000, respectively. Among the patients aged 0-74 years, the cumulative mortality rate was 15.03%. The crude cancer mortality rate in urban areas was higher than that of rural areas. However, the age-standardized rate in rural areas was higher than that of urban areas. Cancers of lung, stomach, esophagus, liver, female breast, colorectum, cervix, brain, uterus and ovary were the most common cancers, accounting for about 82.80% of all cancer new cases. Lung cancer, stomach cancer, esophageal cancer, liver cancer, colorectal cancer, female breast cancer, brain cancer, leukemia, pancreatic cancer and cervix cancer were the leading causes of cancer deaths, accounting for about 88.50% of all cancer deaths. The burden between urban and rural, males and females were different. Conclusions: Registration data of Henan province was qualified to provide basic information on population-based cancer incidence, mortality for cancer prevention and control. The upper digestive tract cancer burden in Henan province, especially for males in rural areas, was higher. The incidence rate of female breast cancer was higher in urban areas. Targeted prevention, early detection and treatment programs should be carried out by health department to control the cancer burden. 展开更多
关键词 Cancer registry INCIDENCE MORTALITY EPIDEMIOLOGY henan province
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A New Sauropod Dinosaur from the Late Cretaceous Gaogou Formation of Nanyang,Henan Province 被引量:5
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作者 ZHANG Xingliao Lǔ Junchang +6 位作者 XU Li LI Jinhua YANG Li HU Weiyong JIA Songhai JI Qiang ZHANG Chengjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第2期212-221,共10页
A new sauropod dinosaur Baotianmansaurus henanensis gen. et sp. nov. from the Cretaceous Gaogou Formation of Neixiang, Henan Province is erected. It is characterized by somphospondylous presacral vertebrae; a highly-d... A new sauropod dinosaur Baotianmansaurus henanensis gen. et sp. nov. from the Cretaceous Gaogou Formation of Neixiang, Henan Province is erected. It is characterized by somphospondylous presacral vertebrae; a highly-developed lamina system on the dorsal vertebrae; transverse process supported by four laminae; and the dorsal portion of the anterior centroparapophyseal lamina is bifurcated, with a small branch extending to the ventral surface of the prezygapophysis. It represents a new titanosauriform sauropod. 展开更多
关键词 Titanosauriform Baotianmansaurus Gaogou Formation Late Cretaceous Nanyang henan province
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Regional agricultural landscape pattern changes along the Yellow River in Henan Province from 1987 to 2002 被引量:5
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作者 LIANG Guofu DING Shengyan LI Zhiheng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第4期415-422,共8页
Agricultural landscape along the riparian zones is designated as important landscape components for partly controlling water quality, biodiversity, as well as for their aesthetic role in landscapes. Therefore, the cha... Agricultural landscape along the riparian zones is designated as important landscape components for partly controlling water quality, biodiversity, as well as for their aesthetic role in landscapes. Therefore, the change of agricultural landscape along the riparian zones is at the top of the agenda for many policy makers and landscape planners. As a basis for conservation management, sufficient information about landscape structure should be provided. In the present study, we reconstructed the former landscape structure and elucidated the changes in landscape patterns during a period of about 15 years. Two sets of maps were used: a landsat-5 TM image (1987) and landsat-7 ETM image (2002). The frequency index, landscape diversity index and landscape fragmentation index were calculated for analyses. The results showed that: (1) the areas of the irrigated land, river, forest and beach landscape classes presented a decreasing trend while the areas of landscape classes of pool, paddy fields, dry land and construction land increased. (2) Disturbed by human activity, landscape diversity index increased but landscape fragmentation index decreased. In short, Human activities have had important influences on agricultural landscape of the riparian zones along the Yellow River in Henan Province. 展开更多
关键词 agricultural landscape landscape pattern change the Yellow River henan province
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Dynamics of forest biomass carbon stocks from 1949 to 2008 in Henan Province,east-central China 被引量:5
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作者 Yanfang Wang Ling Liu Zhouping Shangguan 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期434-443,共10页
We estimated forest biomass carbon storage and carbon density from 1949 to 2008 based on nine consecutive forest inventories in Henan Province,China.According to the definitions of the forest inventory,Henan forests w... We estimated forest biomass carbon storage and carbon density from 1949 to 2008 based on nine consecutive forest inventories in Henan Province,China.According to the definitions of the forest inventory,Henan forests were categorized into five groups: forest stands,economic forests,bamboo forests,open forests,and shrub forests.We estimated biomass carbon in forest stands for each inventory period by using the continuous biomass expansion factor method.We used the mean biomass density method to estimate carbon stocks in economic,bamboo,open and shrub forests.Over the 60-year period,total forest vegetation carbon storage increased from34.6 Tg(1 Tg = 1×10;g) in 1949 to 80.4 Tg in 2008,a net vegetation carbon increase of 45.8 Tg.By stand type,increases were 39.8 Tg in forest stands,5.5 Tg in economic forests,0.6 Tg in bamboo forests,and-0.1 Tg in open forests combine shrub forests.Carbon storageincreased at an average annual rate of 0.8 Tg carbon over the study period.Carbon was mainly stored in young and middle-aged forests,which together accounted for 70–88%of the total forest carbon storage in different inventory periods.Broad-leaved forest was the main contributor to forest carbon sequestration.From 1998 to 2008,during implementation of national afforestation and reforestation programs,the carbon storage of planted forest increased sharply from 3.9 to 37.9 Tg.Our results show that with the growth of young planted forest,Henan Province forests realized large gains in carbon sequestration over a 60-year period that was characterized in part by a nation-wide tree planting program. 展开更多
关键词 Forest biomass carbon stock Forest resource inventory henan province
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Geography and Rural Household Income:A Village Level Study in Henan Province,China 被引量:4
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作者 LI Xiaojian FAN Xinsheng 《Chinese Geographical Science》 SCIE CSCD 2010年第1期1-8,共8页
This study uses the data from a sample survey conducted in April 2007 on 1 251 rural households in 11 villages of Henan Province, the largest less developed agricultural province in China, to examine how geography aff... This study uses the data from a sample survey conducted in April 2007 on 1 251 rural households in 11 villages of Henan Province, the largest less developed agricultural province in China, to examine how geography affects rural household income (RHI). The quantitative analysis indicates following results. I) The significance of the traditional geographical factors reduces as RHI rank increases. 2) The landform does not affect the RHI significantly. The per capita income of rural household in a plain area is lower than that in a mountainous area. And 3) the capital endowment and status of non-farm economic activities contribute to the increase of RHI. But the probability and intensity of non-farm economic activities of rural households in urban outskirts villages are higher than that in non-urban outskirts villages. Based on the results, the paper further concludes that geography still plays a significant role in rural development, but it is changing over time. The agricultural resources (such as per capita arable land) significantly affect RHI with the relatively lower income level, while the geographical location shows a more significant impact on RHI with the relatively high income level. Along with economic development, the proximity replaces the traditional geographical factors such as landform and physical resources as the major determining factor in RHI. 展开更多
关键词 rural household income (RH1) geographical factor village level study henan province
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